The camera has one small, slow chip and very little memory to do that interpolation. Your computer has a big, powerful processor and lots of memory, not to mention, no particular need to compromise their software routines to fit into a small amount of memory or trade quality for speed to avoid long delays after taking a picture. In short, your computer will do a vastly better job at interpolating the picture than your camera will, and to top that off you can choose different algorithms (often named after the mathematicians or programmers who created them, like Lanczos or Mitchell) and experiment with how well they work on a particular image. You can even save different versions of the file, including the original, which you can't if the camera is doing the work. There's nothing to be gained by compromising image quality, which is exactly what you're doing if you don't use the best filter you can get your hands on. The interpolated image even takes up more space on your camera's memory card, but it doesn't hold any more information than the original. Finally, as I mentioned above, it adds time between shots, as the camera has to grind away at reshaping your picture before you can take another one.
You can use your photo editing software or even many picture viewers or dedicated programs, to view and copy EXIF data. It can also be used by specialized software provided by the camera manufacturer when loading pictures into your computer to record information about camera settings and even provide editing options. One of the things these transfer programs can do is to change the timestamp of the newly created file to match the time the photo was taken. That's another good reason to set the clock on your camera to the correct time. This data can be used to record a log of photographs for a variety of purposes. The time a favored shot was taken may be referred to later in duplicating light conditions. You can keep track of settings for experimenting with changes in settings, and never get your pictures mixed up because the data is stored as part of the file itself. You can export or copy the EXIF information and not have to manually enter information in your log.
What is it that is actually capturing the image? Where film cameras have a roll of film exposed behind the aperture, digital cameras have a sensor. Most digital cameras use an array of photo sensors under a filter matrix which results in the sensors each recording red (8-12 bit), green (8-12 bit) or blue (8-12 bit) light intensities. These separate sensors or channels create what is often referred to as the Bayer matrix pattern where every other sensor records green with the alternating cells recording in red or blue. Each pixel in a conventional sensor only captures one color. This data is typically 10 or 12 bits per pixel, with 12 bits per pixel currently being most common. Most cameras now provide the option to instantaneously store the captured material in a RAW file while alternatively the camera's processor can weave the RAW data using all three color channels to provide an instant 24 bit full-color JPEG or TIFF display image. RAW is not an abbreviation but literally means "raw" or "unprocessed". A RAW data file contains the original image information as it comes off the sensor before in-camera processing so you have a variety of choices in processing the data on your PC using one of many editing software programs available.
Analog or film cameras use the term ASA speed, however it is important to remember that a single digital camera can capture and store images at several ISO speeds. Amplifying the image signal in a camera can also amplify noise and thereby higher ISO speeds may produce progressively more noise in the photo. The character of an image in a photo can also change noise. Where lighter areas in analog or film photos tend to have the most noise, it is the darker areas of digital photographs that have the largest amount of noise. Digital cameras produce three types of noise called random noise, fixed pattern noise and banding noise. Random noise describes the abnormal intensity of color fluctuations compared to the rest of the photograph. It is most influenced by the ISO speed however the pattern of random noise may change even if exposure settings remain the same. Random noise may be the least objectionable, but the most difficult to remove where the noise is too often mistaken for true image characteristics. Fixed Hot pixels or fixed pattern noise describe pixel intensity that far exceeds that of ambient random noise fluctuations.
If you are looking to turn your pictures into pieces of art, there are many options available to you, as well. You can turn your print into a black and white picture and hand color some details. You can create beautiful special effects that will really make your digital photo stand out in a crowd, too. As you can image, the tools to create the perfect picture can cost a lot of money, if you have to purchase them. If you are on a budget, or just like to save money, anything you can find for free is a bonus! Well, there are free photo editors out there, you just have to look for them. Since the introduction of the Internet, there are literally thousands upon thousands of pages of information that are geared specifically toward helping you achieve the pictures of your dreams. You don't have to spend one penny to edit your photographs. All you need is access to a computer and scanner and you are well on your way. Just log onto any one of the number of free photo editor applications available and a whole new world of editing possibilities will be right at your fingertips. Don't let your money, or lack of, keep you from making the best pictures, just download some freeware and start editing your own pictures!
At the opposite end of the spectrum, you can take advantage of the extremely short duration of the flash in low-light situations. Flash firing time can be as short as 1/50,000 of a second, and while the camera's CCD sensor will remain active longer than that, almost all of the light in a dark scene that reaches the CCD will be from that flash event. This can effectively "freeze" the action as if you were using a shutter speed faster than your camera can support. Small built-in flash units have a very short "reach," often providing effective light only as far as two or three meters. This weakness, however, can be turned into a strength if you think about how you want to compose your scene. Certainly for "isolating" or emphasizing your subject, the ability to move only a short distance from background objects and radically reduce their light level is handy. In night shots outdoors or low-level indoor shots, the "weaker" flash gives more control over the content of the shot by dramatically reducing the "foreground" and magnifying the effect of distance.
Secure Digital (SD) cards were designed to replace the older MMC standard - but it's beginning to look like the reverse may happen. The good news is that SD cards are available in larger sized - up to 4 Gigabytes, and higher speeds than MMC cards currently are. In theory, SD cards are the fastest on the market. In practice, it's almost a dead heat with Compact Flash cards. The bad news is that SD cards are losing market share rapidly, though they are still used in many cameras. The better news is that if the MMC standard takes over, full-size MMC cards can be used in SD slots. Compact Flash (CF) is one of the oldest and most popular standards available today. They have the widest range of sizes (up to 8 Gigabytes with larger microdrive-based cards rumored) and are quite quick. Currently they compete only with SD cards for the high-end camera market, and their position looks more secure than SD. New developments in wireless transfer support for cameras and links to external drive packs may cement CF cards' place.